What is dual marking, and do I need it?

Why you'd print two barcodes

Not every checkout scanner in the world can read a 2D barcode yet. GS1's Sunrise 2027 target is about getting most point-of-sale systems to that point by the end of 2027 — see our Sunrise 2027 explainer for the honest version of what that target does and doesn't require. Until 2D reading is close to universal at checkout, a brand that wants the benefits of a 2D code (a page that opens on a phone, room for more information than a UPC can hold) still needs its existing 1D barcode to scan reliably everywhere it already sells. Dual marking is printing both, together, during that transition.

What goes on the package

Your existing UPC or EAN barcode stays exactly as it is — same placement, same size, same printer settings you already use. The 2D code (QR or GS1 DataMatrix) is added as a second, separate symbol, encoding the same GTIN.

The one thing to get right: keep them apart

The main layout mistake is placing the two symbols close enough that a scanner's aiming beam or camera frame can catch both at once, or close enough that a cashier can't tell by eye which one they're aiming at. Give each barcode its own clear quiet zone — the blank margin GS1 specifies around a symbol so a scanner can distinguish where it starts and ends — and enough separation from the other symbol that there's no ambiguity about which one is being scanned. As a rule of thumb, more separation than feels necessary is safer than less; a specific minimum gap in real-world units depends on your symbol sizes, so check it against your printed proof rather than eyeballing the artwork on screen.

Sizing and contrast still matter, separately, for each symbol

Dual marking doesn't relax the normal rules for either barcode. Each symbol needs to be printed large enough to scan reliably at the distance and lighting of a real checkout, with its own full quiet zone, in dark ink on a light background — never inverted (light code on a dark background), which is unreliable for most scanners. If you're unsure whether your planned print size is large enough, check it against a size calculator before sending artwork to print, not after.

When you can stop dual marking

There's no fixed calendar date for this. The honest answer is: once point-of-sale scanners at the retailers you sell through reliably read 2D codes, and you've confirmed that with them directly — not before. GS1 describes the crossover as gradual, tied to actual scanner upgrades at retail, not a single cutover day. If a specific retailer you sell through tells you they no longer need your 1D barcode, that's their call to make, not a general rule you can assume applies elsewhere.